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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_000_001_203">&nbsp;</a>NAME</h4><blockquote>
assert - insert program diagnostics
</blockquote><h4><a name = "tag_000_001_204">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="assert.h.html">assert.h</a>&gt;

void assert(int <i>expression</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_000_001_205">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>assert()</i>
macro inserts diagnostics into programs.
When it is executed, if
<i>expression</i>
is false (that is, compares equal to 0),
<i>assert()</i>
writes information about the particular call that failed
(including the text of the argument, the name of the source file
and the source file line number - the latter are respectively
the values of the preprocessing macros __FILE__ and __LINE__)
on
<i>stderr</i>
and calls
<i><a href="abort.html">abort()</a></i>.
<p>
Forcing a definition of the name NDEBUG,
either from the compiler command line or with the
preprocessor control statement
<b>#define NDEBUG</b>
ahead of the
<b>#include &lt;assert.h&gt;</b>
statement,
will stop assertions from
being compiled into the program.
</blockquote><h4><a name = "tag_000_001_206">&nbsp;</a>RETURN VALUE</h4><blockquote>
The
<i>assert()</i>
macro returns no value.
</blockquote><h4><a name = "tag_000_001_207">&nbsp;</a>ERRORS</h4><blockquote>
No errors are defined.
</blockquote><h4><a name = "tag_000_001_208">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_001_209">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_001_210">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_000_001_211">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="abort.html">abort()</a></i>,
<i><a href="stderr.html">stderr</a></i> ,
<i><a href="assert.h.html">&lt;assert.h&gt;</a></i>.
</blockquote><h4>DERIVATION</h4><blockquote>
Derived from Issue 1 of the SVID.
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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